Fontana saw the need to develop a new artistic language at a time when technological progress was constantly producing new insights and inventions. He felt that this could be achieved primarily through the use of new artistic means. In addition to the "buchi", he also used glass and sand to create a three-dimensional surface, as in Concetto spaziale, rosso e pietre (1954).
The outer part of the canvas is painted dark red and contains seven red splinters, while the centre is an orange area worked with sand and interspersed with eight blue glass splinters. The canvas is also perforated with a series of holes. Fontana also used glitter and sequins in other works in the 'pietre' ('stones') series. The surface reflects light in different ways, creating different visual effects and evoking associations with twinkling stars and constellations. The texture of the surface and the contrasts of material and colour create a three-dimensional effect.
In addition to the "buchi", from 1952 Fontana developed the series of pietre (stones), gessi (chalk pastels), inchiostri (ink pictures) and barocchi (baroque pictures). These include the black and grey 'Concetto spaziali' of 1957, in which Fontana uses sand and a kind of sequin that makes the surface shimmer almost imperceptibly. The sand may symbolise the earthly, but in our imagination it can also be the material or the body-forming substance of other planets; the glittering, star-like sparkle, on the other hand, leads to cosmic vastness.
But we also see a dynamic figurative form here. That the association with the human body is not far-fetched becomes clear when Fontana, albeit jokingly, has himself photographed in a moving pose in front of the work. Dynamic, expansive and endowed with a restrained decorative splendour, it expresses a vitality that can be seen as a modern, contemporary variant of Baroque spatial art.